Fundamentals of Front End Development MCQs with Answers
Practice important Fundamentals of Front End Development MCQs with answers and explanations.
Chapter: 82
Q921:
Fill in the blank: The debugger keyword is used to _____ the execution of JavaScript and invoke the debugging function.
A. pause
B. continue
C. resume
D. stop
Correct Answer:
A
Chapter: 82
Q922:
How can you set breakpoints in JavaScript code?
A. By using the debugger keyword
B. By using the console.log() method
C. By manually editing the code
D. By using the built-in debugger tools in the browser
Correct Answer:
D
Chapter: 82
Q923:
Which of the following methods is used to display JavaScript values in the debugger?
A. alert()
B. console.log()
C. prompt()
D. document.write()
Correct Answer:
B
Chapter: 82
Q924:
Fill in the blank: To activate debugging in Google Chrome, you need to press _____ and select "Console" in the debugger menu.
A. F12
B. F10
C. F8
D. F5
Correct Answer:
A
Chapter: 82
Q925:
What happens when you set a breakpoint in JavaScript code?
A. Code execution stops at the breakpoint
B. Code execution continues without interruption
C. The browser automatically fixes the error
D. The code is optimized
Correct Answer:
A
Chapter: 82
Q926:
Which browser tool should you use for debugging in Firefox?
A. Developer Tools
B. Firebug
C. Console
D. Inspect Element
Correct Answer:
B
Chapter: 82
Q927:
Fill in the blank: To enable the "Develop" menu in Safari, go to Preferences, Advanced, and check "Enable Show Develop menu in _____".
A. menu bar
B. status bar
C. toolbar
D. settings
Correct Answer:
A
Chapter: 82
Q928:
How can you display JavaScript values in the debugger window using the console.log() method?
A. By assigning values to variables
B. By calling the console.log() method with the values
C. By using the alert() method
D. By using the document.write() method
Correct Answer:
B
Chapter: 82
Q929:
What is the effect of the debugger statement in JavaScript when debugging is turned on?
A. It stops the execution of JavaScript before the next line is executed
B. It continues the execution without stopping
C. It logs the code to the console
D. It fixes errors automatically
Correct Answer:
A
Chapter: 82
Q930:
Which menu option should you select in Opera to add a Developer Console button?
A. Tools
B. Developer Tools
C. Console
D. Extensions
Correct Answer:
D
Chapter: 82
Q931:
Fill in the blank: To open the debugging tools in Internet Explorer, you need to select _____ from the menu.
A. tools
B. developer tools
C. console
D. options
Correct Answer:
B
Chapter: 83
Q932:
Why should global variables be avoided in JavaScript?
A. They can be overwritten by other scripts
B. They are faster than local variables
C. They are easier to manage
D. They do not cause errors
Correct Answer:
A
Chapter: 83
Q933:
Fill in the blank: Local variables should be declared with the _____ keyword to avoid becoming global variables.
A. var
B. let
C. const
D. global
Correct Answer:
A
Chapter: 83
Q934:
What is a potential issue with declaring numbers, strings, or booleans as objects?
A. It speeds up execution
B. It improves code readability
C. It slows down execution and produces side effects
D. It prevents type conversions
Correct Answer:
C
Chapter: 83
Q935:
What should be used instead of new Object() in JavaScript?
A. {}
B. new Object()
C. ""
D. new String()
Correct Answer:
A
Chapter: 83
Q936:
Fill in the blank: To avoid automatic type conversions, it's important to _____ your variables.
A. convert
B. initialize
C. declare
D. check
Correct Answer:
B
Chapter: 83
Q937:
What is the recommended way to create an empty array in JavaScript?
A. new Array()
B. []
C. new Object()
D. {}
Correct Answer:
B
Chapter: 83
Q938:
Fill in the blank: The practice of declaring variables at the top of a function or script helps to reduce the possibility of unwanted _____ variables.
A. global
B. local
C. primitive
D. string
Correct Answer:
A
Chapter: 83
Q939:
Fill in the blank: It is best to treat numbers, strings, or booleans as _____ values rather than objects.
A. primitive
B. object
C. array
D. function
Correct Answer:
A
Chapter: 83
Q940:
What is one of the drawbacks of using new Boolean(false) in JavaScript?
A. It can create performance issues
B. It improves code clarity
C. It makes type conversions easier
D. It speeds up execution
Correct Answer:
A